Cement production ultra-clean discharge system and process method

The invention provides an ultra-clean emission system and process method for cement production. The ultra-clean emission system comprises an ERD + fire coal saturated steam catalytic combustion denitration module, a denitration agent conveying and spraying module, a tail exhaust flue gas purification module and a control module. The conveying efficiency of a denitration agent is improved through the heavy screw conveyor and the Roots blower, after saturated steam is introduced, the combustion speed of pulverized coal is increased, meanwhile, the concentration of a reducing agent in the reduction areas is increased, the reaction time of nitric oxide and the reducing agent is prolonged through the two reduction areas, and therefore the denitration efficiency is improved; through two-stage purification of the absorption spraying layer and the water washing spraying layer of the purification tower, the effect of treating ammonia escape is improved to a great extent, environmental pollution is effectively reduced,